Video compression algorithms, such as those standardized by the standardization organizations ITU, ISO, and SMPTE, exploit the spatial and temporal redundancies of images in order to generate bit-streams of data of smaller size than original video sequences. These powerful video compression tools, known as spatial (or intra) and temporal (or inter) predictions, make the transmission and/or the storage of video sequences more efficient.
Video encoders and/or decoders (codecs) are often embedded in portable devices with limited resources, such as cameras or camcorders. Conventional embedded codecs can process at best high definition (HD) digital videos, i.e 1080×1920 pixel frames.
Real time encoding is however limited by the limited resources of the portable devices, especially regarding slow access to the working memory (e.g. random access memory, or RAM) and regarding the central processing unit (CPU).
This is particularly striking for the encoding of ultra-high definition (UHD) digital videos that are about to be handled by the latest cameras. This is because the amount of pixel data to encode or to consider for spatial or temporal prediction is huge.
UHD is typically four times (4 k2 k pixels) the definition of an HD video which is the current standard definition video. Furthermore, very ultra high definition, which is sixteen times that definition (i.e. 8 k4 k pixels), is even being considered in a more long-term future.